Field of the Invention
This invention relates generally to Universal Serial Bus (USB) Type-C ports and, more particularly, to increasing data throughput for a USB Type-C port of a computing device.
Description of the Related Art
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
A dock may be connected to a computing device (e.g., an information handling system) to provide additional ports, such as, for example, one or more of a video port, an audio port, a data port, or another type of input/output (I/O) port. In some cases, the dock may be attached to the computing device via a USB port, such as USB type-A (“USB-A”). In other cases, to increase throughput compared to USB-A, the dock may be attached to the computing device using a proprietary connector, such as a Dell® E-connector (a bottom mount interface).
As computing devices adopt the use of USB Type-C (“USB-C”) ports, users may desire to connect a dock via a USB-C port. However, USB-C has several limitations, such as expense and a limited number of lanes for carrying traffic. For example, a dock may use Multi-Function DisplayPort (MFDP) mode to provide a USB3 (USB 3.1 or higher compliant) channel and two lanes of DisplayPort (DP). This type of capability is suited for entry-level users that want to dock relatively low (e.g., 1920×1080 pixels or lower) resolution monitors. For medium-level performance users, a Thunderbolt™ port providing 40 gigabits per second (Gbps) may be used to provide a dock supporting two 4K (e.g., 3840×2160 pixels or greater) resolution monitors along with additional USB devices. However, using a Thunderbolt™-based dock is relatively expensive. A first Thunderbolt™ chip in the computing device provides a protocol tunneling service for protocols such as DP, USB, and Peripheral Component Interconnect Express (PCIe). Because the signal is transmitted 20 Gbps, a second Thunderbolt™ chip in cable is used to re-drive the signal to support a cable length of 1 meter. A third Thunderbolt™ chip in the dock converts the Thunderbolt™ signaling back to the original protocols (e.g., DP, USB, and PCIe). Thus, three Thunderbolt™ chips are required for a dock resulting in relatively expensive solution.
In addition, USB-C has a limited amount of throughput because a maximum of four different signals are possible over four differential pairs. For example, for high-level performance users, a USB-C docking solution that provides relatively high resolution (e.g., 5K and 8K) monitors and relatively high refresh rates is currently unavailable. Applications, such as virtual reality, may use 4K resolution with 120 Hz refresh rate (×2 for two eyes). However, the bandwidth to support such applications is beyond the capability of a USB-C or Thunderbolt™-3 interface using current signaling schemes.